Relationship of LDL Particle Size to IMT and Insulin Resistance in Non-Diabetic Adult

Park, Jina; Kim, Chul Sik; Park, Jong Suk; Kim, Dol Mi; Cho, Min Ho; Kong, Jee Hyun; Kim, Hai Jin; Kim, Jeong Ho; Ahn, Chul Woo; Kim, Kyung Rae; Cha, Bong Soo; Lim, Sung Kil; Lee, Hyun Chul

Abstract

BACKGROUND: The aims of this study were to investigate the predictor of the low density lipoprotein(LDL) particle size and the relationship of the LDL particle size to the levels of insulin resistance and the carotid intima-media thickness (IMT) in healthy Koreans.
METHODS
The subjects were 47 and 89 clinically healthy males and females, aged between 32 and 70years, without medications that could potentially alter glucose and lipid metabolisms. The mean LDL particle size was determined by polyacrylamide tube gel electrophoresis(Lipoprint(r) LDL, Quantimetrix), the insulin resistance using a short insulin tolerance test kit, and the subclinical atherosclerosis from the carotid intima-media thickness.
RESULTS
The LDL particle size was found to be significantly correlated with insulin resistance using a simple Pearson's correlation(r=0.233, P<0.01), but the independent predictors of the LDL particle size, as determined by a multiple stepwise regression analysis, were serum triglyceride(TG), high density lipoprotein(HDL) cholesterol level and age(beta=-0.403, P=< 0.001; beta=0.309, P=0.003; beta=-0.219, P=0.016, respectively). Significant relationships were found between an increasing IMT and the traditional risk factors of atherosclerosis: age, LDL cholesterol, HDL cholesterol, systolic and diastolic blood pressure(r=0.490, P<0.001; r=-0.251, P<0.01; r=0.211, P<0.05; r=0.298, P<0.01; r=0.263, P<0.01, respectively). However, no significant correlation was found between an increasing IMT and the LDL particle size (r=-0.172, P=0.075).
CONCLUSION
The best predictors for the LDL particle size were the serum TG level, HDL cholesterol level and age. Insulin resistance was not found to be an independent predictor of the LDL particle size. Small dense LDL was not found to be a predictor of the IMT in healthy Koreans.